package com.atguigu.chapter07;

import com.atguigu.bean.WaterSensor;
import com.atguigu.util.MyUtil;
import org.apache.flink.api.common.eventtime.*;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.api.functions.windowing.ProcessWindowFunction;
import org.apache.flink.streaming.api.windowing.assigners.TumblingEventTimeWindows;
import org.apache.flink.streaming.api.windowing.time.Time;
import org.apache.flink.streaming.api.windowing.windows.TimeWindow;
import org.apache.flink.util.Collector;

import java.util.List;

/**
 * @Author lizhenchao@atguigu.cn
 * @Date 2021/6/11 14:39
 */
public class Flink10_Watermark_Custom {
    public static void main(String[] args) {
        Configuration conf = new Configuration();
        conf.setInteger("rest.port", 20000);
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(conf);
        env.setParallelism(1);
        env.getConfig().setAutoWatermarkInterval(0); // 设置为0 就关闭了周期性的发射水印
        
        env
            .socketTextStream("hadoop162", 9999)
            .map(line -> {
                String[] data = line.split(",");
                return new WaterSensor(
                    data[0],
                    Long.valueOf(data[1]) * 1000,
                    Integer.valueOf(data[2]));
            })
            .assignTimestampsAndWatermarks(
                new WatermarkStrategy<WaterSensor>() {
                    @Override
                    public WatermarkGenerator<WaterSensor> createWatermarkGenerator(WatermarkGeneratorSupplier.Context context) {
                        return new MyPeriodWMS();
                    }
                }
                    .withTimestampAssigner(new SerializableTimestampAssigner<WaterSensor>() {
                        @Override
                        public long extractTimestamp(WaterSensor element, long recordTimestamp) {
                            return element.getTs();
                        }
                    })
            )
            .keyBy(WaterSensor::getId)
            .window(TumblingEventTimeWindows.of(Time.seconds(5)))
            .process(new ProcessWindowFunction<WaterSensor, String, String, TimeWindow>() {
                @Override
                public void process(String key,
                                    Context ctx,
                                    Iterable<WaterSensor> elements,
                                    Collector<String> out) throws Exception {
                    List<WaterSensor> list = MyUtil.toList(elements);
                    
                    out.collect("key=" + key +
                                    ", window=[" + ctx.window().getStart() / 1000 + " , " + ctx.window().getEnd() / 1000 +
                                    ", 元素个数: " + list.size() +
                                    ")");
                }
            })
            .print();
        
        try {
            env.execute();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    public static class MyPeriodWMS implements WatermarkGenerator<WaterSensor> {
        
        long maxTs = Long.MIN_VALUE + 3000 + 1;
        
        // 每来一条数据执行一次
        @Override
        public void onEvent(WaterSensor event, long eventTimestamp, WatermarkOutput output) {
            System.out.println("MyPeriodWMS.onEvent");
            maxTs = Math.max(maxTs, eventTimestamp);
            output.emitWatermark(new Watermark(maxTs - 3000 - 1));
        }
        
        // 周期性(200ms)的执行:
        @Override
        public void onPeriodicEmit(WatermarkOutput output) {
            System.out.println("MyPeriodWMS.onPeriodicEmit");
//            output.emitWatermark(new Watermark(maxTs - 3000 - 1));
        }
    }
}
